Solar-assisted patch cart

ABSTRACT

A solar energy-assisted patch cart with a support surface for carrying and heating bituminous materials, a heating source located adjacent to the support surface, and a battery powered at least in part by solar energy for igniting a burner associated with the heating source. Preferably, a charge controller is used to maintain the battery with a predetermined level of charge. The solar energy may be supplied by one or more retractable solar panels in electric communication with the battery.

BACKGROUND OF THE INVENTION

The present invention relates to the field of patch carts used forpatching roadways. More specifically, the invention is directed to asolar power-assisted patch cart.

Generally, patch carts are used by towns, cities, municipalities,counties, or states to repair local roadways, highways or parking lotfacilities, for example. In addition, private entities may use thesepatch carts to repair roadways or facilities. Patch carts include anenclosure for storing bituminous material such as asphalt used for roadrepair. The enclosure and bituminous material are heated, and thenselectively dropped onto a repair area, such as by release from thebottom portion of a funnel-shaped patch cart, or by shoveling. Suitablepatch carts which may be used in connection with the present inventioninclude asphalt patch carts such as those sold by SpauldingManufacturing, Inc., of Saginaw Michigan (www.spauldingmfg.com).

Past patch carts have employed several methods of heating the asphalt,for example, including diesel burner systems. Diesel systems may bepreferred for safety reasons because they do not require large storagecontainers of volatile propane to be attached to the patch cart. Dieselsystems also may be preferred for convenience because of the relativeease of refilling diesel fuel tanks versus refilling propane tanks.Electric-powered patch carts are also available, but these require agasoline engine-powered generator to run the electric.

A variety of commercially-available, asphalt-based materials containingbituminous materials and chemicals, including UPM (having a meltingtemperature or T_(m) of about 80° F.), HotMax (T_(m) of about 220° F.),and ColdPatch (T_(m) of about 180° F.) may be used in such patch carts,which typically require about 45 minutes-1 hour to heat these materialsto their melting temperatures prior to their use on roadways. When theasphalt material reaches its melting temperature, a temperature sensorin connection with a solenoid valve, for example, shuts off the burner.A battery (typically 12 volts) located on the patch cart is then used toignite the burner and continue heating of the asphalt after apredetermined period and/or after sensing that the asphalt's temperaturehas dropped below its melting temperature by a predetermined amount.This burner ignition and shut-off, and corresponding temperaturecycling, continues throughout the day, including during transport of thepatch cart from job-site to job-site.

A problem frequently encountered with conventional patch carts is thatduring cycling, the patch cart battery often loses charge and does nothave sufficient charge to ignite the burner. When this happens, thebattery must be charged in the field, either by using a portable batterycharger, or by using the battery on the truck used to transport thepatch cart. Alternatively, the patch cart must be returned to itsoriginal location and its battery replaced with a new battery.

Given its frequent use throughout a working day, the patch cart batterywill quickly lose charge over time if not re-charged. A 12-volt batterywill provide an average of about 550 cranking amps at 32° F., while atleast 16 amps are typically need to ignite the burner. (As an example,about three hours of burner ignition, requiring re-lighting (at 70° F.)about every 20 minutes, in this environment will normally be sufficientto deplete the battery below the amperage necessary to reignite theburner.) Maintaining the charge of the patch cart battery above thatnecessary to ignite the burner by using the battery of the truck used totransport the patch cart can be problematic because of the distancebetween the front of the truck (where the truck battery is located) andthe burner system on the patch cart located at the rear of the truck.For example, 4 amps may be dissipated over 15 feet if a 10-gaugecable/wire is used. Pick-up trucks, for example (often used to transportpatch carts) often carry cable/wire (e.g., 14 gauge wire) which is toothin to effectively charge the battery. The patch cart battery may alsolose power due to blown fuses or relays on the towing vehicle, or thedriver shutting off the towing vehicle but not the patch cart (e.g,during break or lunch time).

Accordingly, it would be desirable to provide a cost-efficient patchcart with a battery that is readily charged, providing a reliable burnersystem.

SUMMARY OF THE INVENTION

The objects mentioned above, as well as other objects, are solved by thepresent invention, which overcomes disadvantages of prior patch carts,while providing new advantages not believed associated with suchdevices.

In a preferred embodiment of the present invention, a solarpower-assisted patch cart is provided. The patch cart includes a supportsurface for carrying and heating a bituminous material, such as asphalt,suitable for paving or repairing roadways. The patch cart also includesa heating source, such as diesel or propane fuel, to heat the supportsurface and bituminous material within the support surface. The patchcart further includes a solar-assisted battery for use in igniting aburner associated with the heating source. Preferably, a chargecontroller in electrical communication with the battery is provided, tofacilitate maintaining the battery with a predetermined level of charge.

In an alternative embodiment, a sufficient number/size of solar panel(s)may be used, preferably in combination with a battery booster, to powernot only burner ignition but also the burner/engine itself.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features which are characteristic of the invention are setforth in the appended claims. The invention itself, however, togetherwith further objects and attendant advantages thereof, will be bestunderstood by reference to the following description taken in connectionwith the accompanying drawings, in which:

FIG. 1 is a perspective view of the patch cart of the present inventionshowing the solar panels in an exposed, energizing mode;

FIG. 2 is an enlarged perspective view of an upper portion of the patchcart shown in FIG. 1;

FIG. 3 is a view similar to FIG. 2 illustrating the solar panels in aretracted, rest mode;

FIG. 4 is a rear perspective view of the upper portion of the patch cartshown in FIG. 3;

FIG. 5 is a side perspective view of the patch cart of the presentinvention attached to the rear of a vehicle pulling the patch cart;

FIG. 6 is an enlarge view of the slidable pin and channel on support bar25 shown in FIG. 3; and

FIG. 7 is a front and side perspective view of a conventional dieselburner, in partially unassembled form.

DEFINITIONS OF CLAIM TERMS

The terms used in the claims of the patent as filed are intended to havetheir broadest meaning consistent with the requirements of law.

“Bituminous” means any of a variety of particulate materials, includingbut not limited to the material commonly referred to as “asphalt,” whichmay be used to repair road surfaces.

Where alternative meanings are possible, the broadest meaning isintended. All words used in the claims are intended to be used in thenormal, customary usage of grammar and the English language.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Set forth below is a description of what are believed to be thepreferred embodiments and/or best examples of the invention claimed.Future and present alternatives and modifications to this preferredembodiment are contemplated. Any alternatives or modifications whichmake insubstantial changes in function, in purpose, in structure, or inresult are intended to be covered by the claims of this patent.

FIG. 1 shows a preferred embodiment of the patch cart of the presentinvention, generally referred to by the reference numeral 15. Patch cart15 includes a container or enclosure 20 which may have funneling,sloping sides 21 and an interior support surface (not shown). Asphalt oranother bituminous material suitable for repairing roadways may beloaded into the patch cart enclosure 20 and carried on the inner supportsurface.

Still referring to FIG. 1, patch cart 15 may include a fire extinguisher80, a heat exhaust 100, a diesel tank(s) located in an enclosure 60, anda computer 40 for controlling various operations as further describedbelow. Alternatively, propane gas stored in cylinders, for example, maybe used to heat the enclosure 60. A battery 50 (FIG. 5) may be used toignite the burner for the diesel or propone fuel. Patch cart 15 may beattached to the rear of a vehicle 90 as shown in FIG. 5.

Referring to FIG. 7, a conventional diesel burner 140 for ignitingdiesel fuel to heat the patch cart is shown in partially unassembledform. Diesel burner 140 may include electric components 141, a blowermotor 142, igniters 143, an injector 145, and a fuel pump assembly 147.

Referring now to FIGS. 1 and 4, in a particularly preferred embodiment abattery charge controller 30 in electrical communication with battery 50may be used to control charge to battery 50, as further explained below.Battery 50 and charge controller 30 are preferably solar powered, suchas by solar panels 35, and are in electrical communication with thesolar panels for this purpose. Battery 50 may be used to ignite aburner(s) associated with the fuel source used to heat enclosure 20.

While solar panels are commercially available, in a preferred embodimentit was found to be cost-effective to use solar panels that hadpreviously been used for that purpose as arrow markers by the statehighway authority. Alternatively, commercially available solar panelswhich may be used include, for example:

12 volt, 4.55 amps: http://www.solar-electric.com/bpso80wasopa.html

12 volt. 7.1 amps: http://www.solar-electric.com/bpso125wasop.html

To avoid contact with asphalt loaded in the patch cart, solar panels 35may be retracted, as shown in FIGS. 3-5. For this purpose, solar panels35 may be allowed to rotate or fold relative to the patch cart, such asrelative to inner and outer pairs of vertical support bars 25, 26 andhorizontal support bar 27, which may be attached to the side of patchcart enclosure 20. Referring to FIGS. 3 and 6, for this purpose channels25 a, 25 b may be provided within support bar 25, so that a slidable pin25 c may move within these channels between locked and unlockedpositions. Providing solar panels 35 with a retraction or foldingcapability allows the solar panels to remain out of the way duringloading of the patch cart.

Preferably, solar panels 35 may be placed in electrical communication,such as by hard wiring, to a battery charge controller 30, shown in FIG.4. The battery charge controller 30, such as the Solar Charge Controllerand Power Booster from Advanced Energy Group, prevents overcharging ofthe battery system 50, shown in FIG. 5, in daylight, and also preventsdrainage of the battery at night, such that the battery may bemaintained with a predetermined level of charge. In an alternativeembodiment of the invention, multiple solar panels may be used inconjunction with a charge controller and booster, to enable the patchcart to be fully solar powered, such that power assist from the towingvehicle is not required.

The heating mechanism initiated by the battery system 50 may be any of anumber of types of heating mechanisms well known in the art. One suchsuitable heating mechanism known in the art is a fuel such as dieselfuel. Another suitable heating mechanism known in the art is propanefuel. Another suitable heating mechanism known in the art is an electricpowered heating system.

In an alternative embodiment, a sufficient number/size of solar panel(s)may be used, preferably in combination with a battery booster, to powernot only burner ignition but also the burner/engine itself. For example,with a diesel-powered Spaulding patch cart it was found that about 16amps were necessary to power the diesel burner heating the patch cart.Each solar panel referenced above provides about 3 amps of current.Accordingly, using two or more solar panels for powering a 12-voltbattery, in conjunction with a battery booster, provides sufficientcurrent to power the diesel burner without need for power assist fromanother vehicle.

Other changes and modifications constituting insubstantial differencesfrom the present invention, such as those expressed here or others leftunexpressed but apparent to those of ordinary skill in the art, can bemade without departing from the spirit and scope of the presentinvention and without diminishing its attendant advantages; It is,therefore, intended that such changes and modifications be covered bythe following claims.

1. A solar energy-assisted patch cart, comprising: a heat-conductivesupport surface adapted to carry and heat a bituminous material placedwithin the patch cart; a heating source located adjacent the supportsurface, for heating the support surface and, by heat conduction, thebituminous material; and a battery powered at least in part by solarenergy for igniting a burner associated with the heating source.
 2. Thesolar energy-assisted patch cart of claim 1, wherein the battery is inelectrical communication with one or more solar panels.
 3. The solarenergy-assisted patch cart of claim 2, wherein the solar panel(s) arelocated in a retractable fashion adjacent the patch cart, whereby whenthe patch cart is loaded with the bituminous material, the solarpanel(s) may be inclined in a position to substantially avoid contactwith the bituminous material as it is loaded.
 4. The solarenergy-assisted patch cart of claim 1, wherein the heating sourcecomprises a fuel.
 5. The solar energy-assisted patch cart of claim 4,wherein the fuel comprises diesel fuel.
 6. The solar energy-assistedpatch cart of claim 1, wherein the bituminous material comprisesasphalt.
 7. A solar energy-assisted patch cart, comprising: aheat-conductive support surface adapted to carry and heat a bituminousmaterial placed within the patch cart; a heating source located adjacentthe support surface, for heating the support surface and, by heatconduction, the bituminous material; a battery powered at least in partby solar energy for igniting a burner associated with the heatingsource; and a charge controller in electrical communication with thebattery, to facilitate maintaining the battery within a predeterminedlevel of charge.
 8. The solar energy-assisted patch cart of claim 7,wherein the charge controller provides voltage control.
 9. The solarenergy-assisted patch cart of claim 7, wherein the charge controllerprovides current limit control.
 10. The solar energy-assisted patch cartof claim 7, wherein the charge controller comprises a photovoltaiccharge controller.
 11. The solar energy-assisted patch cart of claim 7,further comprising a power booster in electrical communication with thebattery.
 12. The solar energy-assisted patch cart of claim 7, furthercomprising a volt/amp meter in electrical communication with thebattery.
 13. A solar energy-assisted patch cart, comprising: aheat-conductive support surface adapted to carry and heat a bituminousmaterial placed within the patch cart; a heating source located adjacentthe support surface, for heating the support surface and, by heatconduction, the bituminous material; and solar panels in electricalcommunication with the heating source for selectively powering ignitionand maintenance of the heating source.